1. Technical Field
The invention relates to a seat particularly for a wheeled carriage, chair or the like
The seat referred to here can be used in wheeled carriages, i.e. baby carriages, in particular pushchairs, and also wheelchairs for disabled people, in particular disabled children or young people, or can be used in chairs. The seat can preferably be folded up so that it can be stored in a space-saving manner when not in use (for example, in a car).
2. Prior Art
Known seats of the type mentioned at the beginning have a pivotable backrest. The backrest can be pivoted from an upright or virtually upright position, in which the children or disabled people adopt an upright sitting position, into a completely or virtually horizontal position, in which the children or young children can recline. Particularly whenever the seat accommodates severely disabled young people, the weight of the said young people leads to a noticeable shift in the center of gravity of the person in the seat with respect to the underframe of a wheeled carriage, a chair or the like when the backrest is adjusted from a reclining position into the sitting position. This shift in the center of gravity results in the risk of the wheeled carriage, chair, or the like tipping over.
Starting from the above, the invention is based on the object of providing a seat particularly for children and/or disabled people, in which the risk of tipping over of the wheeled carriage or chair provided with the seat is eliminated.
A seat for achieving this object has the features claimed herein. By virtue of the fact that when the backrest of the seat is pivoted, the position of the seat surface is changed, a shifting in the center of gravity of the person in the wheeled carriage, the shifting being caused by the pivoting of the backrest, can be compensated for. Accordingly, a shift in the center of gravity, which leads to the wheeled carriage, chair, or the like tipping over, takes place only to an insignificant extent, if at all.
The seat is preferably designed in such a manner that pivoting of the backrest enables the seat surface, and in particular also the backrest, to be displaced along a preferably straight path with respect to an underframe of the wheeled carriage or with respect to a chair frame, such as a supporting frame, for example. By this means, virtually the entire seat is displaced with respect to the supporting frame if, by pivoting of the backrest, the person sitting in the seat is raised from a reclining position or vice versa. The person in question is thereby displaced together with the seat in such a manner that the center of gravity of the person is always located in such a position with respect to the underframe, chair frame or the like that the frames cannot tip over.
According to a preferred embodiment of the invention, the seat, in fact particularly together with the seat surface, is mounted displaceably on preferably two parallel guiding members. The guiding members form guiding paths that preferably run approximately horizontally. However, they can also slope away slightly to the foot end of the person sitting in this seat, as a result of which raising the person by folding the backrest upwards is facilitated.
Provision is furthermore made for connecting the backrest pivotably to the seat surface. This preferably takes place by means of two tilting bearings that are assigned on opposite sides at least to one part of the seat surface, in particular, in a fixed manner. The backrest is coupled pivotably to the tilting bearings; specifically by pivot points, the pivot points of the two spaced-apart tilting bearings lying on a common, imaginary pivot axis which runs in a horizontal direction transversely with respect to the direction of movement of, for example, the wheeled carriage. The pivotable coupling of the backrest to the seat surface makes it possible to displace the entire seat, but preferably only at least one part of the seat surface, with respect to the supporting frame. To this end, the tilting bearings are mounted displaceably in or on the guiding members.
According to an advantageous embodiment of the invention, base parts and guiding paths, the base parts being longitudinally displaceable on the guiding paths form the guiding members. To this end, the base pans are preferably designed as sleeve-like guides that surround the guiding paths. The base parts also have other functions: one for thing, they serve, with the assistance of corresponding coupling means to fasten the seat and the guiding paths to the supporting frame, for example to an underframe of the wheeled carriage. This takes place in accordance with a further inventive concept for which independent protection is claimed, which enables the seat together with the guiding paths and base parts to be separated from the supporting frame. For another thing, the base parts serve to change the distance of a footrest, which is fastened to the guiding paths, with respect to the backrest, in order to adapt the depth of the seat to children or young people differing in size.
The guiding paths can be formed from preferably straight guiding rods. These guiding rods are expediently rigid in all directions. In addition, it is also conceivable to form the guiding paths from chains or profiles which are flexible or elastic in one direction. The rigid properties of the chains or profiles suffice in order to guide the seat, in particular at least one part of the seat surface, displaceably in a defined manner. In another direction, which preferably runs perpendicularly with respect to the direction in which the chains or profiles are rigid, the chains or profiles are elastic or flexible. This enables the guiding paths to be kept comparatively short because that part of the said paths which is not required at a given instant for guiding the seat can be moved out of the actual guiding path.
According to a preferred embodiment of the seat according to the invention, the backrest is connected to at least one base part via a coupling element. It is preferable if at least one coupling element is provided between the backrest and each base part. The particular coupling element is coupled at a distance from the pivot point of the corresponding tilting bearing for connecting the backrests to the seat surface. This has the result that when the backrest is pivoted about the swivel points on the tilting bearings, the coupling elements which are supported on the base parts displace the tilting bearings together with the pivot points, and the position of the seat surface with respect to the underframe or another supporting frame is changed. Because the backrest is coupled to the seat surface, the backrest joins in with the positional change of the seat surface or of part of the said seat surface. However, this movement is combined with the tilting movement of the backrest, as a result of which a relative movement is brought about between the backrest, on the one hand, and the seat surface, on the other hand. This change in the position of the backrest and the seat surface leads to the seat, to be precise essentially only the seat surface or at least part thereof, adopting a changed position, so that the center of gravity of the person sitting or reclining in the seat does not change, or does not change significantly, with respect to the supporting frame in the horizontal direction, and this avoids there being the risk of the wheeled carriage, chair or the like tipping when the backrest is pivoted and the position of the person sitting or reclining in the seat changes as a result.
According to a preferred embodiment of the invention, the or each coupling element is coupled to the backrest and to the relevant bass part in such a manner that when the seat is folded up, i.e. the backrest is pivoted onto the seat surface, the particular coupling element perpendicularly intersects with the (imaginary) rotational axis running through the swivel points of the tilting bearings. This has the effect that when the backrest is initially folded onto the seat surface, the seat is moved in the one direction, and when the backrest is completely folded onto the seat surface, the said seat is moved back in the opposite direction. The result is that the folded-up seat takes up particularly little space.